Chain magazine for holding machining tools

ABSTRACT

The invention concerns a chain magazine designed to hold the machining tools for machining devices, in particular tooling machines. The magazine comprises a continuous chain fitted with holder devices for the machining tools and driven by at least two sprockets and guided by guide elements up to the point of contact with the pitch diameter of the drive or guide sprocket wheel. The chain magazine further comprises chain links consisting of a connecting bar and, joined to the bar, two tubular sleeve elements of different diameter which form the flexible couplings between the links. Holder devices for machining tools are disposed coaxially to the hinge axes in the mutually encircling tubular sleeves under a small motion clearance. Shaft-like cutouts are furnished in each of the tubular sleeves and exhibiting parallel faces disposed spaced apart and directed toward the center axes of the holder devices. Said cutouts form an open insertion channel or, respectively, removal channel in the respective insertion position or, respectively, removal position of the chain hinge. The respective (outer) tubular sleeve, which surrounds the (inner) tubular sleeve of a smaller diameter, exhibits in a sector of its circumference a recess of the thickness of the connecting bar.

The invention relates to a chain magazine for receiving of machiningtools for machining devices, in particular, tooling machines. Chainmagazines of this kind comprise essentially a continuous chain with toolholders and at least two sprocket wheels as well as guide elements forthe chain links following to the reference circle diameter of the guidesprocket wheel.

Such chain magazines are known, for example, from the German PrintedPatent Document DE-OS 2,000,779. The hinges connecting the chain linksare formed of hollow cylindrical shape in the chain magazine shown inthe German Printed Patent Document DE-OS 2,000,779 and the hinges areformed as tool holders. This is associated with the consequence that thetools can only be inserted or, respectively, withdrawn in the directionof the hinge axes of the hollow cylinders connecting the chain links.

The last recited disadvantage is avoided in a chain magazine known fromthe German Printed Patent Document DE-OS 2,525,212 A1. The tool holdersare disposed at chain link plates according to the German Printed PatentDocument DE-OS 2,525,212 A1, which chain link plates are hingedlyconnected to each other by receiving free chain link plates. The centerlink plates of the tool holders therefore describe path curves, wherethe path curves exhibit a substantial distance from the path curves ofthe link pins. Because of the free intermediate chain link plates, thereceiving capacity is limited to half of the chain links present. Inparticular, it is a disadvantage in this context that high torquesoccur, in particular, upon a start-up and braking because of thedistance of the path of motion of the tools from the curve of the pathof the chain proper, which situation should be avoided.

The German Printed Patent Document DE 3,431,091 C2shows a magazine ofthis kind, where each chain link plate is furnished centered between thelink pins with a tool holder. While according to this, the path ofmotion of the axes of the tool holders is placed closer to the pathcurve of the chain, there remains nevertheless still a disadvantageousdistance causing torques associated with the individual motion of thetools.

Therefore, the object is to provide such a chain magazine for machiningdevices, where the axes of the tool holders run precisely in the curveof the path of the chain, and which allows the discharge of the tools ina direction perpendicular to the axes of the tools or, respectively, ofthe tool holders.

The solution according to the invention is associated with the followingfeatures starting with a chain magazine of the recited kind:

a) chain links are formed by a connecting bar and two tubular sleeves ofdifferent diameters connected at two ends of the connecting bar to theconnecting bar and forming the chain hinges,

b) holder devices for machining tools are disposed coaxially to thehinge axes (Z) in the mutually encircling tubular sleeves under a smallmotion clearance, as well as

c) shaft-like cutouts are furnished in each of the tubular sleeves andexhibit parallel faces disposed spaced apart and directed toward thecenter axes of the holder devices, wherein the tubular sleeves form anopen insertion channel or, respectively, removal channel in therespective insertion position or, respectively, removal position of thechain hinge.

The idea on which the invention is based starts with the considerationthat large acceleration forces acting on the chain links and on thetools inserted in the holder devices are to be avoided. These forces andtorques occur in particular based on jumps in acceleration upon thetransition from a straight into a curved path section of the chaintransport and vice versa, and these forces and torques increase with asquare dependence in case of an increased transport speed. Therefore, itis advantageous if the axis of the tool coincides with the axis of thechain hinge. If the hinge axis of the chain does not coincide with thepath of motion of the tools, then very high acceleration forces andtorques occur, in particular in case of high transport speeds and veryhigh acceleration forces and torques cause premature wear of the chainor of the holder device.

It is furthermore advantageous that the tool and chain hinge axescoincide because a dense loading of the chain can be realized with thetools disposed at a small distance, and where nevertheless a chain canbe realized with extremely small curve radii. In a chain magazine,according to the German Patent DE 3,431,091 C2there occur increasedacceleration forces and torques based on the connecting bars having acourse which is secant-shaped and inwardly directed in the curved partsections, for example in the region of the sprocket wheels, on the onehand, because of the deviation of the path of motion of the axes of thetools from the path of motion of the chain links and, on the other hand,the smallest possible curve radius is limited based on the necessaryspaces between the tools. The separation distance of the chain links isdetermined in case of the chain magazine of the present invention by thelargest tool diameter. The guide sprocket wheels can be reduced to bemade up of only two sprockets. Transport speeds of up to 100 m/min orbeyond are possible without that the acceleration forces and thecentrifugal forces and the torques become too large. This makes veryshort tool change times possible.

The insertion position or, respectively, the removal position of thechain hinge can be adapted to the requirements of the machine. Dependingat which position of the adjoining chain links the cutouts in thetubular sleeves are brought to overlap and thereby form the insertionchannel or, respectively, the removal channel, the removal of the toolis possible on a straight or angular path region of the course of thechain.

An essential feature of the invention comprises that the respective(outer) tubular sleeve engaging into the space width between thesprockets of the sprocket wheel, which tubular sleeve encircles the(inner) tubular sleeve of a smaller diameter, exhibits along a sector ofits circumference a recess of the thickness of the connecting bar.

The recess allows the mutual hinged rotatability of chain linksadjoining to each other in the case of a simultaneously coaxiallyextending course of the connecting bar.

A further embodiment feature can comprise that the sprocket wheels areformed of two sprocket wheel disks disposed at a distance to each other.The two bilaterally free (outer) tubular sleeves of larger diameterengage into the two sprocket wheel disks. The connecting bars of thechain run between the two sprocket wheel disks. This is associated withthe advantage of an improved chain guide accepting torques and providingan increased directional stability.

Advantageously, the tubular sleeves, forming the hinges and engaginginto the space widths between the sprockets of the sprocket wheel, areconnected to form a single piece with the connecting bar. Thisconstruction allows a low-cost assembly of the chain.

It can further be provided that the tubular sleeves forming the hingesand engaging into the space widths between the sprockets of the sprocketwheel, are connected to each other by a connecting bar comprising twospaced-apart chain link plates such that the two connecting bars of thechain link surround the sprocket wheel on two sides.

According to a further advantageous feature, it is proposed that theconnecting bars are furnished with guiding rollers. The guiding rollersserve in a conventional way for the direction-stabilized guiding of thechain along guide rails.

The chain magazine is also furnished in a conventional way with clampingmembers for the disengageable support of the tool shaft or of the toolcone in the holder devices for the machining tools.

Appropriately, it can be advantageous for decreasing the wear of thehinges, if in each case the outer (larger) tubular sleeve, surroundingthe inner tubular sleeve of a smaller diameter, is furnished with trackrollers received by the space widths between the sprockets of thesprocket wheels.

The advantages of a chain magazine according to the invention ascompared to the state of the art comprise the possibility of insertionand removal of the tools in a direction perpendicular to the axes of thetools at an arbitrary position of a straight or curved part section ofthe course of the chain and, in particular, also the possibility ofloading the chain densely with tools in case of simultaneously shortchain links and narrow courses of curves, as well as the possibility ofrunning very high transport speeds for achieving the shortest toolchange times while avoiding undesirably high acceleration forces andcentrifugal forces and torques.

The following embodiments of the invention allow to recognize furtheradvantageous features and characteristics, where the advantageousfeatures and characteristics are described in more detail and explainedby way of the schematic representations in the drawings in thefollowing. There is shown in

FIG. 1 a perspective view of a chain link with the respectivebilaterally hinged chain links shown as a part representation;

FIG. 2 a section A-B through the chain link illustrated in FIG. 1;

FIG. 3 a section C-D through the chain link illustrated in FIG. 1;

FIG. 4 a perspective view of the part of the chain magazine, which isguided around a four-sprocket two-disk sprocket wheel;

FIG. 5 a schematic side view of the view according to FIG. 4;

FIG. 6 a schematic section E-F through the view according to FIG. 5;

FIG. 7 a chain link according to a first embodiment;

FIG. 8 a chain link according to a second embodiment;

FIG. 9 a chain link according to a third embodiment;

FIG. 10 a side view according to FIG. 6 with two removal directions;

FIG. 11 a side view according to FIG. 6 with one removal direction;

FIG. 12 a side view according to FIG. 6 with two removal directions;

As can be recognized from FIG. 1, the hinges 13 are in each case formedby two chain links 9, coupled to each other, where a chain link 9 ineach case is formed by two tubular sleeves 11, 12, guiding each othermutually and sliding in each other, where the tubular sleeves areconnected to each other with the connecting bar 10. This connection canbe made of one piece as illustrated, however, also out of severalpieces, for example by two chain link plates leaving an intermediatefree space. As can be recognized further from FIG. 1, the connecting bar10 is cranked in order to be able to hold the axial extension of thetubular sleeves 11, 12 shorter and in order to create nevertheless spacefor the engagement of the sprockets 5 of the sprocket wheel asillustrated in FIG. 3.

Furthermore, the tool 8 to be inserted is recognized in FIG. 1 togetherwith a gripper groove 7, where the clamping members 6 engage into thegripper groove 7 (compare FIG. 3).

A recess of the thickness h of the connecting bar 10 is placed in thesector 14 of the outer tubular sleeve 12 surrounding the inner tubularsleeve 11 of a smaller diameter. This recess allows a deflection of theconnecting bar 10 of the following chain link 9; this deflection amountsfor example to 45° in case of the four-sprocket sprocket wheel 3illustrated in FIG. 6; in case of a sprocket wheel with six sprockets,this deflection would be 30°.

The section A-B according to FIG. 2 shows in axial view (tool axis z)or, respectively, coordinate axes 19, the tubular sleeves 11, 12engaging each other, where the tubular sleeves 11, 12 are connected byway of the connecting bar 10. Furthermore, the cutouts 20 of the tubularsleeve 11 and cutouts 21 of the tubular sleeve 12, formed by parallelfaces, are recognizable, which cutouts 20, 21 form in case of acorresponding alignment--compare FIG. 4 and 5--the insertion channel or,respectively, the removal channel 23 for the tool 8.

The chain link 9 is shown in FIG. 3 in a sectional view C-D; theillustrated elements are furnished with the already recited referencenumerals, and it is indicated by dashed lines in which region thesprockets 5 of a single-disk-shaped sprocket wheel encircle in part thetubular sleeves 12.

It can be recognized from the illustration in FIG. 4 how four chainlinks 9 are engaged by an intermediate sprocket wheel comprising thedisks 3 and 30, where the sprockets of the intermediate sprocket wheelare designated with 5, and where the spaces between the sprockets of theintermediate sprocket wheel are designated with 4. It can be recognizedthat insertion positions and removal positions 23 (Zu/En) for tools canbe obtained in two positions, if--compare FIG. 12--the cutouts 20, 21are disposed as illustrated for example in FIG. 9.

The view of FIG. 5 shows the embodiment according to FIG. 4 in a sideview. In case of an example with a four-sprocket sprocket wheel, it ismore clearly recognizable, that in a first insertion position or,respectively, a removal position (Zu/En), a removal channel 23 isdisposed at an angle of 90° relative to the straight advance directionof the chain, and in a second insertion position or, respectively,removal position (Zu/En) at an angle of 135° relative to the straightadvance direction of the chain 2, and in fact in dependence on theselected angle positions α and β of the cutouts 20, 21 in the tubularsleeves 11, 12.

The section E-F according to FIG. 5, illustrated in FIG. 6, allows torecognize in the example according to FIG. 4 that the disks 30 and 3 ofthe sprocket wheel engage with their sprockets 5 or, respectively, theirspaces 4 between the sprockets 5 bilaterally into the tubular sleeves 1,12 of the chain links 9.

The representations 7-12 show three configurations of chain links 9 fora chain magazine according to the invention with four-sprocket sprocketwheels according to the embodiments of FIGS. 1-6. These configurationsare characterized by a very small space requirement, and thisconfiguration allows a precise guiding of the tools in the magazine.

The configuration of the chain link 9a as shown in FIG. 7 allows thetwo, insertion and removal, positions in the y-axis and at 45° relativeto the y-axis (respectively 135° relative to the straight advancedirection of the chain 2), which two insertion and removal positions areillustrated in FIG. 10. in correspondence to the FIGS. 4 and 5. Here theangle α for the cutout 21 in the tubular sleeve 12 amounts to 90° andthe angle β for the cutout 20 in the tubular sleeve 11 amounts to 135°.

The angle α of the cutout 21 amounts to 45°, and the angle β of thecutout 20 amounts to 90° according to the configuration shown in FIG.9b; with this embodiment, the insertion position and the removalposition (Zu/En) in the y-axis and at 45° to the y-axis can be achievedas illustrated in FIG. 12; these positions are inverted relative to thepositions according to FIG. 10.

Only one insertion position or, respectively, removal position can beachieved with the cutouts 20, 21 inclined by 45° at the angle α in thetubular sleeve 12 and inclined by 135° for the angle β in the tubularsleeve 11 as illustrated in FIG. 9c, i.e. in the x-axis as can berecognized from FIG. 11.

Five positions for the removal of tools can be achieved with the threeillustrated configurations of the cutouts 20, 21 according to FIGS. 7through 9. If intermediate positions are also to be made possible, thenthe cutouts 20, 21 have to receive correspondingly deviating anglepositions α and β.

I claim:
 1. A chain magazine for receiving of machining tools formachining devices, in particular tooling machines, comprisingacontinuous chain furnished with holder devices for machining tools anddriven by at least two sprocket wheels, wherein the continuous chain isguided by way of guide elements up to reference circle diameters of thesprocket wheels; chain links (9) comprising a connecting bar (10) andtwo tubular sleeves (11, 12) of different diameters connected at twoends of the connecting bar (10) to the connecting bar (10) and formingchain hinges (13), and wherein the holder devices for machining tools(8) are disposed coaxially to hinge axes (Z) in the mutually encirclingtubular sleeves (11, 12) under a small motion clearance; shaft-likecutouts (21, 22) furnished in each of the tubular sleeves (11, 12) andexhibiting parallel faces disposed spaced apart and directed towardcenter axes (19) of the holder devices, which cutouts (21, 22) form achannel (23) corresponding to the respective position of the chain hinge(13).
 2. The magazine according to claim 1, wherein one respective(outer) tubular sleeve (12), which surrounds one (inner) tubular sleeve(11) of a smaller diameter, exhibits in a sector (14) of itscircumference a recess of a thickness (h) of the connecting bar (10). 3.The magazine according to claim 1, further comprising spaces (4) betweensprockets of the sprocket wheel (3) forming bearings for thehinge-forming (outer) tubular sleeves (12) of larger diameter.
 4. Themagazine according to claim 1, wherein the sprocket wheels (3) comprisetwo spaced-apart sprocket wheel disks (3, 30), wherein the bilaterallydisposed free (outer) tubular sleeves (12) of larger diameter engageinto the sprocket wheel disks (3, 30), and wherein the connecting bars(10) of the chain (2) run between the spaced apart sprocket wheel disks.5. The magazine according to claim 1, wherein the hinge-forming tubularsleeves (11, 12), engaging into spaces (4) between sprockets (5) of thesprocket wheel, are connected as a single piece with the connecting bar(10).
 6. The magazine according to claim 1, wherein the hinge-formingtubular sleeves (12), engaging into spaces (4) between sprockets (5) ofthe sprocket wheel, are connected to each other by way of a connectingbar comprising two spaced-apart chain link plates.
 7. The magazineaccording to claim 6, wherein the two chain link plates of theconnecting bar of the chain links (9) surround the single-disk sprocketwheel (3) on two sides of the sprocket wheel.
 8. The magazine accordingto claim 1, wherein the connecting bars (10) are furnished with guidingrollers.
 9. The magazine according to claim 2, wherein the respectiveouter (larger) tubular sleeve (12), surrounding the inner tubular sleeve(11) of smaller diameter, is furnished with track rollers received byspaces (4) between the sprockets (5) of the sprocket wheels (3).
 10. Themagazine according to claim 1, wherein the holder devices for themachining tools are furnished with clamping members (6) for adisengageable support of the machining tools (8).
 11. A chain magazinefor receiving of machining tools for machining devices, comprisingachain link comprising a connecting bar, a first tubular sleeve, and asecond tubular sleeve, wherein the diameter of the first tubular sleeveis larger than the diameter of the second tubular sleeve, wherein thefirst tubular sleeve is connected to a first end of the connecting barand wherein the second tubular sleeve is connected to a second end ofthe connecting bar wherein the first tubular sleeve is to form with andto encircle another second tubular sleeve a first chain hinge andwherein the second tubular sleeve is to form with and to be encircled byanother first tubular sleeve a second chain hinge and wherein the firstchain hinge and the second chain hinge are furnished with respectivehinge axes; a holder device for a machining tool disposed coaxially tothe hinge axis of one of the chain hinges under a small motion clearancebetween the holder device and the second tubular sleeve; a firstshaft-like cutout furnished in the first tubular sleeve and exhibitingparallel faces disposed spaced apart and directed parallel relative tothe center axis of the holder device; a second shaft-like cutoutfurnished in the second tubular sleeve and exhibiting parallel facesdisposed spaced apart and directed parallel relative to the center axisof the holder device, wherein the first cutout and the second cutoutform respective open insertion channels or, respectively, removalchannels for the holder device in a respective insertion position or,respectively, removal position of the chain hinge.
 12. The chainmagazine according to claim 11 further comprisinga second chain linkcomprising a second connecting bar, a third tubular sleeve, and a fourthtubular sleeve with the first chain link and the second chain linkforming a continuous chain, which is furnished with holder devices formachining tools; a first sprocket wheel for driving the continuouschain; a second sprocket wheel engaging the continuous chain such thatthe continuous chain is guided by way of guide elements up to thereference circle diameters of the first sprocket wheel and of the secondsprocket wheel such that the chain magazine is adapted to toolingmachines.
 13. The chain magazine according to claim 12 furthercomprisinga bearing for the first tubular sleeve formed by anintermediate space disposed between sprockets of the first sprocketwheel.
 14. The chain magazine according to claim 12 wherein the firstsprocket wheel comprises two spaced-apart sprocket wheel disks, whereinthe first tubular sleeve engages into the sprocket wheel disks, andwherein the connecting bar of the chain runs between the twospaced-apart sprocket wheel disks.
 15. The chain magazine according toclaim 12 wherein the first tubular sleeve engages into the space betweenthe two neighboring sprockets of the sprocket wheel, and wherein thefirst tubular sleeve and the second tubular sleeve are connected withthe connecting bar formed as a single piece.
 16. The chain magazineaccording to claim 12 wherein the first tubular sleeve engages into thespace between the two neighboring sprockets of the sprocket wheel, andwherein the first tubular sleeve and the second tubular sleeve areconnected with the connecting bar formed as two spaced-apart chain linkplates and wherein the two chain link plates of the connecting bar ofthe chain link surround the single-disk sprocket wheel on two sides. 17.The chain magazine according to claim 12 further comprisingguidingrollers attached to the connecting bar; track rollers attached to thefirst tubular wheel and received by the space between two neighboringsprockets of the first sprocket wheel.
 18. The chain magazine accordingto claim 11 further comprisinga narrowed sector representing a recess ofa thickness (h) of the connecting bar and disposed in a circumference ofthe first tubular sleeve, which surrounds a fourth tubular sleeve of asmaller diameter.
 19. The chain magazine according to claim 11 furthercomprisingclamping members attached to the holder devices for themachining tools for allowing a disengageable support of the machiningtools.
 20. The chain magazine according to claim 1, wherein the sprocketwheels are guide drive sprocket wheels and wherein the channel (23) isan insertion channel in an insertion position of the chain hinge (13).